The association of five polymorphisms with diabetic retinopathy in a Chinese population.

PURPOSE: To comprehend the etiology of diabetic retinopathy (DR), it is crucial to clarify the genetic susceptibility factors for DR. Previous studies have reported that five single nucleotide polymorphisms (SNPs), including rs9362054 (near the CEP162 gene), rs1990145 (MRPL19), rs10519765 (FMN1), rs237025 (SUMO4) and rs767649 (MIR155HG) were associated with DR. This study was conducted to elucidate the association between the five SNPs and DR in a Chinese Han population. METHODS: A total of 957 individuals with type 2 diabetes mellitus (T2DM) including diabetes mellitus without retinopathy (DNR = 478), nonproliferative DR (NPDR = 384) and proliferative (PDR = 95) were recruited in this study. SNPs were genotyped using the Mass ARRAY MALDI-TOF system. The genotype and allele frequencies were determined using χ2 tests. For genotype and allele risk, odds ratios (OR) and 95% confidence intervals (CI) were calculated. Four genetic models (homozygous, heterozygous, dominant, and recessive) were used to further investigate the link between the five SNPs and DR. RESULTS: There was a statistically significant difference of CEP162 rs9362054 between NPDR and DNR (P = .027, OR = 1.26, 95%CI = 1.03-1.54) and a significant association of SUMO4 rs237025 detected between PDR and DNR (P = .031, OR = 1.45, 95%CI = 1.03-2.02). The association of CEP162 rs9362054 was also observed under the dominant mode (P = .03, OR = 1.35, 95%CI = 1.03-1.77). The association of SUMO4 rs237025 was found under the heterozygous model (P = .03, OR = 1.68, 95%CI = 1.06-2.69) and the dominant model (P = .02, OR = 1.70, 95%CI = 1.08-2.67). No associations of the other three SNPs with NPDR and PDR were detected when compared with DNR under these genetic models. CONCLUSIONS: This study showed that rs9362054 and rs237025 were associated with NPDR and PDR when compared with DNR, suggesting that SUMO4 may be involved in the development of PDR, while CEP162 may be associated with NPDR.

SUMO4 Gene SNP rs237025 and the Synergistic Effect With Weight Management: A Study of Risk Factors and Interventions for MetS.

Aim: Metabolic Syndrome (MetS) is widespread across the world. Gene targeted therapy and risk management are promising approaches for MetS intervention. SUMO4 gene rs237025 polymorphism is related to an increased risk of diabetes, therefore, it is considered a target for the gene polymorphism research of MetS. Methods: A case-control study was performed to study the interaction of rs237025 with MetS and the components of MetS. A 5-years follow-up survey was carried out to elucidate the crosstalk between rs237025 and weight management, and the synergistic effect on MetS. Results: A total of 1,008 MetS patients and 1,047 controls were recruited in this research. By cross-section study, we find that rs237025 is an independent risk factor for increased Waist Circumference (WC), elevated Triglyceride (TG), elevated Fasting Plasma Glucose (FPG), and MetS. Cross-over analysis identifies the interaction of rs237025 and weight management as a risk factor for MetS, the synergistic effects of rs237025 and weight management are negative to WC, TG, and High-density Lipoprotein-cholesterol (HDL-c). Conclusion: SUMO4 gene rs237025 is related to increased risk of MetS, weight management is essential to MetS intervention, especially for patients with rs237025 polymorphism.

Association between the SUMO4 M55V Polymorphism and Susceptibility to Type 2 Diabetes Mellitus: A Meta-analysis.

OBJECTIVE: The aim of this study is to determine whether the SUMO4 M55V polymorphism is associated with susceptibility to type 2 diabetes mellitus (T2DM). METHODS: A meta-analysis was performed to detect the potential association of the SUMO4 M55V polymorphism and susceptibility to T2DM under dominant, recessive, co-dominant (homogeneous and heterogeneous), and additive models. RESULTS: A total of eight articles including 10 case-control studies, with a total of 2932 cases and 2679 controls, were included in this meta-analysis. The significant association between the SUMO4 M55V polymorphism and susceptibility to T2DM was observed in the dominant model (GG + GA versus AA: OR = 1.21, 95% CI = 1.05-1.40, P = 0.009), recessive model (GG versus GA + AA: OR = 1.29, 95% CI = 1.07-1.356, P = 0.010), homozygous model (GG versus AA: OR = 1.41, 95% CI = 1.06-1.56, P = 0.001), and additive model (G versus A: OR = 1.18, 95% CI = 1.08-1.29, P = 0.001), and marginally significant in the heterozygous model (GA versus AA: OR = 1.16, 95% CI = 0.98-1.36, P = 0.080). In subgroup analyses, significant associations were observed in the Chinese population under four genetic models excluding the heterozygous model, whereas no statistically significant associations were observed in the Japanese population under each of the five genetic models. CONCLUSION: The meta-analysis demonstrated that the G allele of the SUMO4 M55V polymorphism could be a susceptible risk locus to T2DM, mainly in the Chinese population, while the association in other ethnic population needs to be further validated in studies with relatively large samples.

SUMO4 163 G>A variation is associated with kidney disease in Indian subjects with type 2 diabetes.

Genetic susceptibility probably plays a role in the development and/or progression of diabetic kidney disease. Small ubiquitin-related modifier 4 (SUMO4) mRNA is expressed in human kidney. Substitution of methionine with valine at codon 55 (M55V) of SUMO4 gene induces higher nuclear factor-kB activity, which is known to mediate the development of kidney disease in individuals with diabetes. We investigated the association between the SUMO4 M55V (rs237025, c.163 G>A) and kidney disease in north Indian subjects with diabetes. A case-control analysis was performed using genomic DNA samples from 216 diabetic patients without nephropathy (DM) and 201 diabetic with nephropathy (DN). The SUMO4 c.163 G>A polymorphism was genotyped using polymerase chain reaction amplification followed by restriction digestion. The duration of diabetes was significantly greater in DN. The genotypic and allelic frequencies were different in DM and DN groups: GG genotype was significantly more frequent in DN as compared to DM (p = 0.018, OR 1.72, 95% CI 1.1-2.7). Similarly the G allele was more frequent in DN compared to DM (p = 0.017, OR 1.4, 95% CI 1.1-1.8). This study suggests that SUMO4 c.163 G>A polymorphism is associated with the susceptibility to diabetic nephropathy in north Indian subjects with type 2 diabetes.

Genetic polymorphisms of NFκB1 -94 del/ins ATTG, NFκB1A 2758 A>G and SUMO rs237025 G>A in psoriasis.

BACKGROUND: Nuclear factor-κB (NF-κB) and small ubiquitin-like modifier (SUMO4) are key transcription factors involved in the regulation of immune responses and apoptosis. The aim of this study is to test for the association of NF-κB and SUMO gene polymorphisms with the susceptibility and severity of psoriasis among Saudi cases. SUBJECTS AND METHODS: This is a case controlled study including 85 Saudi psoriasis patients in addition to 92 matched healthy unrelated controls from the same locality. For all participants, DNA was analyzed by PCR for characterization of NF-κB1 -94 del/ins ATTG, NF-κB IA 2758 A>G and SUMO rs237025 G>A gene polymorphisms. RESULTS: Compared to controls, psoriasis patients showed a non-significant difference for all frequencies of genotypes and alleles of NF-κB1 ins/del, NF-κB1A A>G and SUMO4 G>A polymorphisms (p>0.05). However, cases with the plaque type had significantly higher frequency of the SUMO4 A allele carriage (GA+AA genoytpes) than the guttate type (78.6% vs. 21.4%, p=0.02). The PASI score was also significantly higher among cases with the NF-κB1A AA genotype than other cases (p=0.00). CONCLUSION: Genetic polymorphisms of NF-κB1-94 ins/del ATTG, NF-κB IA 2758 A>G and SUMO4 rs237025 G>A were not associated with the susceptibility to psoriasis vulgaris in Saudi patients. However, it might be associated with the expressivity of the disease in terms of its clinical type and severity.

Association of SUMO4 M55V and -94ins/del gene variants with type-2 diabetes.

AIM: There are two different types of diabetes mellitus, type 1 and type 2, with still unclear molecular mechanisms. In the present study, we aimed to investigate the role of small ubiquitin-like modifier 4 (SUMO4) M55V and nuclear factor kappa B1 (NFKB1)-94del/ins in type-2 diabetes mellitus. MATERIALS AND METHODS: We analyzed SUMO4 M55V and NFKB1-94del/ins variants in 104 patients with type-2 diabetes and 124 healthy controls using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques. RESULTS: The number of SUMO4 M55V MM genotype and M allele carriers was significantly higher in patients compared to the control group; however, no efficiency results were found related to NFKB1-94del/ins polymorphism. CONCLUSION: It was found that SUMO4 M55V polymorphism and type-2 diabetes were significantly associated with a possible SUMO4 region to type-2 diabetes susceptibility. This preliminary study showed that the distribution of SUMO4 M55V and type-2 diabetes mellitus in Turkish patients may form the basis of future research.

Engineering pre-SUMO4 as efficient substrate of SENP2.

SUMOylation, one of the most important protein post-translational modifications, plays critical roles in a variety of physiological and pathological processes. SENP (Sentrin/SUMO-specific protease), a family of SUMO-specific proteases, is responsible for the processing of pre-SUMO and removal of SUMO from conjugated substrates. SUMO4, the latest discovered member in the SUMO family, has been found as a type 1 diabetes susceptibility gene and its maturation is not understood so far. Despite the 14 amino acid differences between pre-SUMO4 and SUMO2, pre-SUMO4 is not processed by SENP2 but pre-SUMO2 does. A novel interdisciplinary approach involving computational modeling and a FRET-based protease assay was taken to engineer pre-SUMO4 as a substrate of SENP2. Given the difference in net charge between pre-SUMO4 and pre-SUMO2, the computational framework analysis of electrostatic similarities of proteins was applied to determine the contribution of each ionizable amino acid in a model of SENP2-(pre-SUMO4) binding, and to propose pre-SUMO4 mutations. The specificities of the SENP2 toward different pre-SUMO4 mutants were determined using a quantitative FRET assay by characterizing the catalytic efficiencies (kcat/KM). A single amino acid mutation made pre-SUMO4 amenable to SENP2 processing and a combination of two amino acid mutations made it highly accessible as SENP2 substrate. The combination of the two approaches provides a powerful protein engineering tool for future SUMOylation studies.